Water-tube boiler.



'No. 725,875. PATENTED APR. 21, 1903.

' D. ROBERTS.

. 1 WATER TUBE BOILER. I APPLIUATI UNFILED SEPT. 22, 1902.

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110.725.875'. PATENTED APR. 21,1903.

1). ROBERTS.

WATER TUBE BOILER.

APPLICATION FILED SEPT. 22, 1902.

no MODEL. 3 sums-sum 2 Wz'tr I bu/emf No. 725,875. PATENTBD APR. 21, 1903.

' D. ROBERTS.

WATER IUBB BOILER.

- APPLICATION FILED SEPT. 22, 1902.

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UNITED STATES PATENT O FICE."

DAVID ROBERTS, OF GRANTHAM, ENGLAND.

WAT'ER-TUBEBQILER.

SPECIFICATION formingpart of Letters Patent No. 725,875, dated April 21, 1903. Application filedSepteinber 22,1902. Serial No. 124,367. (No model.)

To all whom it may concern.-

Be it known that I, DAVID ROBERTS, a subject of the King of Great Britain, residing at Spittlegate Iron Works, Grantham, in the county of Lincoln, England, have invented new and useful Improvements in Water-Tube Boilers or Steam-Generators, of which the following is a specification.

My invention relates to water-tube boilers or steam-generators of the type wherein a se'-' ries of small tubes is connected at the upper and lower ends to drums or cylinders. In boilers of this class as heretofore constructed the tubes have usually been inserted in the curved surfaces of the upper and lower drums in a radial direction, and the tubes themselves have usually been more or less bent or curved, according to the points at which they were connected with the drums, thereby necessitating the use of numbers of differentlyshaped tubes. Furthermore, in erecting such boilers it has generally been necessary to affix or ferrule the tubes into the drums after the latter have been placed in the position which they occupy when in use, and in cleaning out such a boiler it has been necessary for a workman to enter the drums. Also in order to replace a tube the old tube has to be removed and the new inserted from the dues.

The object of my invention is to provide a boiler in which the small tubes can be fixed to the drums or the like before leaving the works and in which the tubes can be cleaned without the necessity for the workman to enter any part of the boiler, this latter being of especial advantage "when a boiler has to be cleaned out within a limited period, as it renders unnecessary the cooling down of the boiler, as is the case when a workman has to enter the same. Furthermore, by my construction tubes can be removed and replaced with much greater facility thanwhen they are curved or bent.

To enable my invention to be fully understood, I will describe it by reference to the accompanying drawings, in which Figure l is a sectional elevation of a boiler made according to the invention. Fig. 2is a partial plan view thereof. Fig. 3 is a section on the line 3 3, Fig. 1; and Fig. 4 is a 'View similar to Fig. l of a modified construction of steam-generator.

Referring first to the arrangement illustrated in Figs. 1 to 3, ais the brickwork body of the boiler, and b is the furnace-grate. cc represent a number of straight tubes which are grouped together, so as to form bundles or sections, as clearly shown, the tubes of each section being connected at the top and bottom to tube-plates in the ends of headers d and e, respectively, the said headers being advantageously, as shown, ofcylindrical form and having their axes parallel with the axes of the small tubes 0 c. d and e is provided with a door, (marked (1 6', respectively,) these doors being of sufficient size to permit of ready access to the interior of the headers. The doors d--that is to say, those fitted to the uppermost headers d'are also so made as to permit of a cleaning bar or tool being passed through all the tubes 0 c from the exterior and also to allow of any tube being removed when necessary and another inserted in itsplace. The adjacent sections composing a complete boiler are connected to each other at the top through the medium of the steam-nipples ff and the water-nipples g g and at the bottom by the water-nipples h it, these nipple connections permitting the free circulation of the water and steam through the whole system.

11 is a steam-drum with which the difierent sections are connected through the medium ofthesteam and water nipples fand g, respectively, the said drum being placed at such a height that the water in the various sections is maintained at about the same level. I wish it to be understood, however, that although I have in the drawings shown aboilerprovided with a steam-drum I can dispense with the said drum, in which event all the sections are directly connected together by means of nipples.

In the arrangement shown in Figs. 1, 2, and 3 I haverepresented four rows of sections, the three front' rows being inclined from top to bottom in the direction from front to back of the boiler and the sections in the alternate rows being staggered, so as to break up the furnace-gases as efficiently as possible. The

Each of the headers sections in the rearmost row are arranged vertically, or approximately so, and the feedwater is supplied to the headers dot the said sections through the pipe 713. By this arrangement any mechanical impurities contained in the feed-water, and which owing to the action of the heat are more or less precipitated on passing to the headers 01 from the pipe 70, will descend through the pipes of these vertical sections into the bottom headers e,which, as indicated in Fig. 1, are made deeper than the other bottom headers. The deposited mud collects in these headers e and is periodically removed through the pipe Z, provided with the blow-off cock n.

In the drawings the top headers (Z of the vertical row of sections are shown connected to the steam-drum above the water-levelonly, although it will be clear that they can be connected thereto below the water-level also, if desired.

In Fig. 4 I have shown my improvements applied to a boiler of the kind described in the specification of former British patent, No. 11,276 of 1900tl1at is to say, to aboiler of the kind having two furnaces b and b, the furnace I) being above the furnace b. In this case I arrange above the lower furnace a series of tubular sections 0, inclined upwardly and backwardly, the said sections being similar to the sections above described and having their front or lower headers 6 connected to the lower headers of the front row of inclined sections by the nipples pp and their upper or back headers 01 cl to the steam-drum through the medium of the nipples or tubes q q.

r r are baffles of brick or other suitable fireresisting material, these baffles being arranged so as to cause the furnace-gases to pursue a sinuous course, as shown by the arrows both in the vertical and horizontal planes, this being effected by staggering the said baffles.

The power of a steam-generator made according to the invention can be varied by altering the number and length of the separate tubular sections. Furthermore, as above mentioned, I can dispense with the steam and water drum and take the steam from one or more of the top headers, preferably the inclined headers farthest from the furnace.

Having now particularly described and ascertained the nature of my said invention and in what manner the same is to be performed, I declare that what I claim is- 1. In a steam-generator the combination of a number of independent tubular sections each having its own headers in axial aline ment therewith, the said sections being inclined from the top in a backward direction, of a number of similar rear vertical sections and of connecting nipples between the various upper headers and between the various lower headers of the sections, substantially as hereinbefore described.

2. In a steam-generator the combination of a number of front water-tube sections, each having its own headers in axial alinement with the tubes, the said sections being inclined from the top in a backward direction, of a number of similar rear vertical sections, of a steam and Water drum, of nipples connecting the various upper headers among themselves and to the steam and water drum and of nipples connecting the bottom headers among themselves,substantially as described.

3. In a steam-generator the combination with a pair of furnaces one arranged above the other, of a number of independent main water-tube sections having headers in axial alinement with the tubes thereof, of a number of auxiliary water-tube sections arranged between the two furnaces and of connecting nipples or tubes between the headers of the auxiliary sections and the headers of the main section, substantially as hereinbefore described.

t. A steam-generator comprising a body a, superposed furnaces b, b, water-tube sections 0, d, e, and 0, d, e, connecting-nipples f, g, h and p, q and baflies r, r, substantially as described and illustrated.

DAVID ROBERTS.

Witnesses:

JOHN E. BOUSFIELD, O. G. REDFERN. 

